Assessment of Healing Potential of Alginate and Chitosan‐Based Biomaterials for Cranial Bone Defects in Experimental Model

The healing of bone defects in the skull vault is a serious clinical problem. The aim of this study is to evaluate the effect of two osteoplastic materials on the healing of a cranial vault experimental defect by computed tomography. Two material systems are analyzed in detail: (i) a sodium alginate-based matrix modified with hydroxyapatite microparticles and zinc ions and (ii) a chitosan-based matrix containing in situ-formed brushite nanoparticles; both sample types were loaded with cholecalciferol (VitD3). A total of 36 rats aged 6 months showed that the alginate-based biomaterial promotes complete healing of the parietal bone defect after 200 days, whereas healing with the chitosan-based biomaterials at that time was not complete. The second objective was to determine the kinetics of VitD3 release from experimental biocomposites using high-performance liquid chromatography. The kinetics of VitD3 release depends on the material's composition: The composite with chitosan prolongs the drug release to 48 h without the so-called "burst release." In the case of the alginate composite, a "burst release" of vitamin D3 is observed during the first 4 h. Both osteoplastic materials show the potential to optimize reparative osteogenesis in an experimental defect of the flat skull bone, although the regenerative potential of the alginate-based biomaterial is higher.